My thoughts on what the Hubble tension really is, based on George Efstathiou’s “To H0 or not to H0?“, arXiv:2103.08723.
After being “away” a few weeks where I used this blog as a conference diary (see TMCC2021 and A (Hubble) Tension Headache), the usual arXiv posts return, covering primordial black holes as (not) dark matter, difficulties in constructing working and realistic early dark energy models, and biases to parameter constraints from the effect of baryonic feedback on the gravitational lensing of the CMB. Enjoy the read!
This week’s entry features the return of the Hubble tension, the first discussion in this blog on the lensing anomaly (Alens tension), and for the second time a discussion on cross-correlations between ultra-high energy cosmic rays and large-scale structure (this time done on real data). As a totally random observation, all three papers discussed this week feature authors which already appeared earlier in this blog. Misha Ivanov already featured on Week 7 (#2), Julien Lesgourgues already featured on Week 11 (again #1!), Marc Kamionkowski already featured on Week 16 (#3), Avi Loeb already featured on Week 15 (#3), and Pavel Motloch already featured with another single-author paper on Week 17 (#3). And no, this is a totally random observation and I’m not trying to imply anything about these authors or the quality of their work (you might want to read my welcome post disclaimers once again), but rather you might start to see some interesting patterns regarding the type of works I am interested in. Enjoy!
This week’s entry features a new ACT CMB lensing cross BOSS CMASS galaxies cross-correlation measurement implementing a new tSZ-cleaning procedure, a new update on the H0 tension and in particular how fifth forces could lower the TRGB-calibrated measurement (besides the usual Cepheid-calibrated one), and finally the return of black hole shadows (in asymptotically de Sitter spacetime). Enjoy and stay safe!
